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- Towards the recovery of by-product metals from mine wastes : an X-Ray absorption spectroscopy study on the binding state of rhenium in debris from a centennial Iberian Pyrite Belt minePublication . Figueiredo, M. Ondina; Silva, Teresa; Veiga, JP; de Oliveira, Daniel Pipa Soares; Batista, Maria JoaoRhenium is a very scarce element, occurring in the Earth's crust mainly carried by molybdenite (MoS2). Due to a very low availability comparative to actual industrial demand, rhenium is nowadays one of the most expensive mineral commodities and an increased interest is focused on exploring residues resulting from a long-term mining, particularly of sulphide ore deposits. It is therefore noteworthy to assign the presence of rhenium (in a concentration up to 3 ppm) in the waste materials from the old sulphur factory at the abandoned mine of São Domingos (Iberian Pyrite Belt, Southeast Portugal), exploited since the Roman occupation of Iberia. Aiming at a potential sustainable recovery of rhenium as a by-product, X-ray near-edge absorption spectroscopy (XANES) was applied to clarify the Re-binding and mode of occurrence by comparing Re L3-edge XANES spectra obtained from mine waste samples (previously fully characterized by X-ray laboratory techniques) with similar spectra collected from Re-rich molybdenites (Mo1-xRexS2) and from Re-O model compounds configuring various valences and coordination environments of rhenium ions. Obtained results are commented, ruling out a possible Re-S binding and rather conforming with the binding of rhenium to oxygen in the analysed mine waste materials.
- Chemical elements variation in leaves with different development stages of Cistus plants from S. Domingos mine area, South PortugalPublication . Batista, Maria Joao; Gonzalez-Fernandez, Oscar; Abreu, Maria Manuela; Carvalho, L.Soils and leaves of Cistus ladanifer L. and Cistus salviifolius L. in different stages of development (young and mature) were sampled in different sites of the S. Domingos mine. The soils are thin and were developed on heterogeneous materials of metallurgical slags, gossanous materials and weathered host rocks. In general, mature leaves have higher concentrations of As, Cu, Fe, Mn, Pb and Zn than young leaves. Nevertheless, in Moitinhos site the young leaves have higher concentrations of As, Cu and Mn than mature leaves. Near the mining buildings C. ladanifer leaves have higher concentrations of As in mature leaves than C. salviifolius. The Pb concentrations in mature leaves are significantly higher and C. ladanifer contain two fold more than C. salviifolius leaves. Cistus plants show different behaviour on the trace elements uptake and translocation. This knowledge is useful in order to implement remediation programs in mine areas of the Mediterranean region using these pioneer plants.
- Avaliação por modelação em SIG da contaminação mineira por drenagem ácida em S. Domingos, Faixa Piritosa, AlentejoPublication . Batista, Maria Joao; Brito, M. G.; Abreu, Maria Manuela; Sousa, A. J.; Quental, Lídia; Vairinho, M. Margarida
- Utilização de imagens hiperespectrais na avaliação da contaminação mineira em S. Domingos, Faixa Piritosa, AlentejoPublication . Quental, Lídia; Brito, M. G.; Sousa, A. J.; Abreu, Maria Manuela; Batista, Maria Joao; Oliveira, Vítor M. J.; Vairinho, M. Margarida; Tavares, T.
- Selenium in wastes from the old mine of São Domingos in southern Portugal (IPB) : already attached to oxygen or retained in relics of former chalcogenide minerals?Publication . Figueiredo, M. Ondina; Silva, Teresa; Veiga, JP; Batista, Maria Joao; Salas-Colera, Eduardo; de Oliveira, Daniel Pipa Soares
- São Domingos mining site - Iberian Pyrite BeltPublication . Matos, João Xavier; Pereira, Zélia; Batista, Maria Joao; de Oliveira, Daniel Pipa Soares
- São Domingos mine wastes phytostabilization using spontaneous plant speciesPublication . Abreu, Maria Manuela; Santos, E. S.; Magalhães, Maria Clara; Batista, Maria Joao
- MINEO Southern Europe environment test site : contamination impact mapping and modelling : final ReportPublication . Quental, Lídia; Bourguignon, Anne; Sousa, António Jorge; Batista, Maria Joao; Brito, M. G.; Tavares, T.; Abreu, Maria Manuela; Vairinho, M. Margarida; Cottard, FrancisABSTRACT: Under the framework of the MINEO project, the abandoned S.Domingos mining area as been selected as representative of Southern Europe Environment to test methods and tools for assessing and monitoring the environmental impact of mining activities using hyperspectral data and other relevant data sets. The S.Domingos mining area, is characterised by a long-term mining activity, since pre-roman times till the 1960’s, and is included in the group of Volcanogenic Massive Sulphide deposits of the Iberian Pyrite Belt. The orebody contained Cu, and also Zn and Pb. Several facilities were developed for mining works and ore transportation, covering an area of 50km2, facilitating dispersion of related pollutants. The main environmental problems can be summarised as related to waste material and their pollutant content (Zn, Pb, Sb, Cu, As, Hg and Cd), acid waters (minimum pH value of 1.7) and associated dispersion, as well as landscape disruption. Hyperspectral images were able to identify mineralogical/chemical dispersion of waste material related to Acid Mine Drainage (AMD) following two approaches: one related to AMD waste material field spectra and the other based on AMD minerals, using standard spectral libraries. The processing techniques used were mainly based on the Spectral Angle Mapper classifier and Mixture Tunned Matched Filtering. Globally, both mapping results obtained, either in AMD waste material either in AMD minerals, were able to detect mineralogical/chemical characteristics of imaged ground data, which were validated by field data. The GIS geochemical modelling allowed the determination of effective AMD area of influence, based in water pH values, using geostatistical methods. The Indicator “Collocate-Cokriging” of the water pH using the distance to the highest correlated AMD waste material (mixed sulphur materials from hyperspectral classification) predicts the AMD dispersion in the area related to that material. This methodology achieved good results and could be applied in new areas using waste material hyperspectral image classification for AMD delimitation area.
- Visita à antiga mina de sulfuretos, São DomingosPublication . Matos, João Xavier; Pereira, Zélia; Batista, Maria Joao; Serrão, J.; Machado, G.; Guita, R.; Barreira, Filipe
- Percursos geológicos e mineiros nas minas de São Domingos e ChançaPublication . Matos, João Xavier; Pereira, Zélia; Batista, Maria Joao; de Oliveira, Daniel Pipa Soares